As leaders of the Group of 20 major economies gather in Turkey for the 2015 summit, campaigners are calling on them to stick to their pledge to stop subsidizing fossil fuels. With the Paris climate summit set for the end of the month, they say it is vital that the world’s richest nations show leadership in combating carbon dioxide emissions.

In 2009, G-20 members pledged to end subsidies for fossil fuels in the form of direct grants or loans, tax breaks or price supports.

Shelagh Whitley of the Overseas Development Institute said they were breaking that promise.

“They have provided $452 billion a year in fossil fuel subsidies just to production,” she said.

Researchers found the U.S. government hands out $20.5 billion worth of subsidies every year, mostly in tax breaks.

But, speaking this month after rejecting plans to build the Keystone oil pipeline from Canada through the United States, President Barack Obama said the United States was leading by example.

“America is now a global leader when it comes to taking serious action to fight climate change, and frankly, approving this project would've undercut that global leadership," he said. "And that's the biggest risk we face — not acting.”

Whitley said the ODI research showed Asia’s biggest economies were subsidizing fossil fuels in different ways.

“Countries like China, Japan and Korea have the highest subsidies through public finance," she said. "And a lot of Japan's and Korea’s money is not going domestically; they may be moving away from fossil fuels at home, but they’re still funding fossil fuel production overseas.”

Whitley said the G-20 should act on its pledge to end fossil fuel subsidies. She also said a shift toward subsidizing renewable energies would have a big impact.

The U.S. and China have jointly prioritized establishing a concrete deadline for phasing out all fossil fuel subsidies as a key task during China’s G-20 presidency in 2016.